Excessive Carbon 1994 Force 40HP?

[Soo Nipi]

What would be the running symtoms of excessive carbon in the combustion chambers? I just wanted to get an idea before I remove the heads to inspect. I know I could try running carbon cleaner through the engine but I've read mixed reviews on this procedure on this site and I'm not sure if that is my problem. IE. No power at wide open throttle. Can't get past 5-10 mph. This engine came from a marine dealer in June and he has it back now but seems stumped also and I'm loosing my confidence in his mechanic even though it free. Thanks,

PS Does anyone have an idea of how to fine the weight of the above engine? It is an electric long shaft. I tried asking on this site before but did not get the answer I needed. I don't what to have to take if off the boat and put it on a scale. I have tired asking marine dealers but they don't seem to know. They estimate 100 to 125 lbs but I need to know for sure? Thanks again !!

 

[steelespike]

Re: Excessive Carbon 1994 Force 40HP?

Check compression,Check plugs they should be a soft brown to black.Not heavy black and not wet or shiny.
Carefully pull the plug wires at idle and note the engines reaction.
Loosen wires first and then remove with insulated pliers.
You should here the spark snapping as you move the wires.
See if the choke helps when you try to go.
The basic design of your motor is no mystery it goes back 40 or 50 years.

 

[roscoe]

Re: Excessive Carbon 1994 Force 40HP?

That motor weighs 170#.

I only know of 2 people on this board that put down the tried and true maintenance decarb, which by the way, is recommended by every outboard manufacturer. Do it, do it often.

How high will the rpm rev when you are underway?

Have you checked compression and spark?

Is there an exhaust snout (tailpipe) in place above the prop?